Rotating electric machine

Abstract

A rotating electric machine is provided and includes a rotor rotating around an axis and a stator concentrically surrounding the rotor. The stator is made up of a plurality of packages of laminations and includes a plurality of axial slots distributed along the inner circumference of the stator for receiving a stator winding. Cooling elements are provided within the stator to remove heat from the stator by a flow of cooling air flowing through said stator. The cooling efficiency and stator design are improved by providing radial and axial channels for the cooling air at the slots by combining packages of laminations with different shapes of the slot cut-outs.

1 . Rotating electric machine ( 10 ), comprising a rotor ( 30 ), rotating around an axis, and a stator ( 11 ) concentrically surrounding the rotor ( 30 ), the stator ( 11 ) being comprised by a plurality of packages (P 1 , P 2 ) of laminations ( 15 ,  16 ) and comprises a plurality of axial slots ( 12 ) distributed along an inner circumference of the stator ( 11 ) for receiving a stator winding ( 18 ), cooling elements ( 13 ,  14 ) are provided within the stator ( 11 ) to remove heat from the stator ( 11 ) by a flow of cooling air flowing through said stator ( 11 ), wherein radial and axial channels ( 13 ,  14 ) for the cooling air are provided at the slots ( 12 ) by combining packages (P 1 , P 2 ) of laminations ( 15 ,  16 ) with different shapes (S 1 , S 2 ) of the slot cut-outs. 
     
     
         2 . Rotating electric machine according to  claim 1 , further comprising first packages (P 1 ) of laminations ( 15 ) with slot cut-outs of a first shape (S 1 ), comprising a first slot area (S 1   a ) adapted to receive the stator winding ( 18 ) and a second slot area (S 1   b ) arranged below and separated from the first slot area (S 1   a ), wherein said second slot area (S 1   b ) defines an axial air collector channel ( 13 ); and second packages (P 2 ) of laminations ( 16 ) with slot cut-outs of a second shape (S 2 ), which each include said first and second slot areas (S 1   a , S 1   b ) and have a width (w) larger than the width of the stator winding ( 18 ) to define radial cooling channels ( 14 ) at one or both sides of the stator winding ( 18 ), said first and second packages (P 1 , P 2 ) are arranged along the axis in an alternating fashion, such that a plurality of radial channels ( 14 ) run through the stator ( 11 ) to open into respective axial air collector channels ( 13 ). 
     
     
         3 . Rotating electric machine according to  claim 1 , wherein said laminations ( 15 ,  16 ) each have slot cut-outs of a first shape (S 1 ), comprising a first slot area (S 1   a ) adapted to receive the stator winding ( 18 ) and a second slot area (S 1   b ) arranged below and separated from the first slot area (S 1   a ), said second slot area (S 1   b ) defines an axial air collector channel ( 13 ), and slot cut-outs of a second shape (S 2 ), which each include said first and second slot areas (S 1   a , S 1   b ) and have a width (w) larger than the width of the stator winding ( 18 ) to define radial cooling channels ( 14 ) at one or both sides of the stator winding ( 18 ), similar laminations are put together in first and second packages (P 1 , P 2 ), said first and second packages (P 1 , P 2 ) are arranged along the axis in an alternating fashion, such that a plurality of radial channels ( 14 ) run through the stator ( 11 ) to open into respective axial air collector channels ( 13 ). 
     
     
         4 . Rotating electric machine according to  claim 2 , wherein each of said first and second packages (P 1 , P 2 ) has the same axial height (h), and every two first packages (P 1 ) alternate with a second package (P 2 ) in axial direction. 
     
     
         5 . Rotating electric machine according to  claim 3 , wherein each of said first and second packages (P 1 , P 2 ) has the same axial height (h), and every two first packages (P 1 ) alternate with a second package (P 2 ) in axial direction. 
     
     
         6 . Rotating electric machine according to  claim 1 , wherein said laminations ( 15 ,  16 ) each have a thickness of less than 1 mm, preferably about 0.5 mm, and each of said first and second packages (P 1 , P 2 ) comprises about 20 to 30 laminations. 
     
     
         7 . Rotating electric machine according to  claim 2 , wherein said laminations ( 15 ,  16 ) each have a thickness of less than 1 mm, preferably about 0.5 mm, and each of said first and second packages (P 1 , P 2 ) comprises about 20 to 30 laminations. 
     
     
         8 . Rotating electric machine according to  claim 3 , wherein said laminations ( 15 ,  16 ) each have a thickness of less than 1 mm, preferably about 0.5 mm, and each of said first and second packages (P 1 , P 2 ) comprises about 20 to 30 laminations. 
     
     
         9 . Rotating electric machine according to  claim 4 , wherein said laminations ( 15 ,  16 ) each have a thickness of less than 1 mm, preferably about 0.5 mm, and each of said first and second packages (P 1 , P 2 ) comprises about 20 to 30 laminations. 
     
     
         10 . Rotating electric machine according to  claim 5 , wherein said laminations ( 15 ,  16 ) each have a thickness of less than 1 mm, preferably about 0.5 mm, and each of said first and second packages (P 1 , P 2 ) comprises about 20 to 30 laminations.